Hello sir.. Tooth pain is due to dental caries that approches pulp ....you need to go for x ray of the concerned teeth to rule out the extension of the carious lesion...If the infection is severe at the root apex taking only pain killer wont give you pain relief ..Antibiotics also need to be taken as prescribed by dentists

Use it thrice a day if the pain is intense or twice a day if the pain is moderate

You can use it thrice a day or try ultracet. Tablet twice a day

Yes if the pain is moderate take it 2 times a day If the pain is intense then take it 3 times a day